PROCESS DOCS

falstad simulation

PCB needle method

Finally I have summarized all in a Blender script. (Added as files for this project)

This create a worm drive (screw and gear) and a nut if you only need screw and nut. You can adjust some usefully tolerances too.

Don't use the addon in your scene. Load this file in another empty scene.
I still need to put a picture on addon to facilitate more comprehension.

The scene have a can of soda to have dimensions reference too.

Enjoy it ;)

Note: This need "Extra Objects" addon

http://www.valvias.com/prontuario-rosca-metrica-din-13.php?m=11

Linear pitch: 1.5mm 

Tooths: 20

Adapt Pitch diameter multiplier to get Outside diameter (10mm)

Creating the screw

Creating the gear

Creating one screw nut

-

Creating the screw axis

Creating the gear axis

Sources:

https://www.metalmecanica-facil.mahtg.com/tsinfycor/calculador-tornillo-sinfin-y-corona.html

http://www.valvias.com/prontuario-rosca-metrica-din-13.php?m=11

https://docs.google.com/spreadsheets/d/1aFcktbNmx7cTsuAU0JgZB2Xayx76sSm1ici_PpTlju8/edit?usp=sharing

CONF adjusting tolerances:

Reduce 10um gear axis diameter

Reduce 10um screw axis diameter

Down 10um nut tooth top  (1.125mm to 1.115mm)

Up 10um nut tooth top (0.375mm to 0.385mm)

Note: Make the same for the nut tooths

Now join the axis tooths

and nut tooths

and gear axis

-

20 tooths = 1:20 (around 75um per 1.5mm step)

reductor multiplier :)

1.5mm/20 = 75um

75um/20 = 3.75um

3.75um/20 = 187.5nm

187.5nm/20 = 9.375nm

If I place more of these I could do a kind of clutch disconnecting 2 and 3 and connecting 1 and 4 when apply some movement of joystick. I will need to handle micro-things in 2D/3D for future projects.